I registered my 3 classes but when I go to instantiate one of the classes, I am told the class isn't registered. REGISTRATION:

public static class M1Register
{
    public static void RegisterAll( ref DomainConfiguration  config)
    {
       config.Types.Register(typeof(M1_DocumentTypes).Assembly, typeof(M1_DocumentTypes).Namespace);
       config.Types.Register(typeof(M1_DocumentElements).Assembly, typeof(M1_DocumentElements).Namespace);
       config.Types.Register(typeof(M1_Documents).Assembly, typeof(M1_Documents).Namespace);

    }
}

===================================================================================== EXCEPTION: System.ArgumentException was unhandled Message=Type 'M1_DocumentElements' is not registered. Source=Xtensive.Orm StackTrace:

   at Xtensive.Orm.Model.TypeInfoCollection.get_Item(Type key)
   at Xtensive.Orm.Key.Create(Session session, Type type)
   at Xtensive.Orm.Entity..ctor(Session session)
   at DTDB.Model.M1_DocumentElements..ctor(Session session) in D:\testbed\AADObj\AADObj\DBDocTracer.cs:line 66
   at DTDB.Program.Main(String[] args) in D:\testbed\AADObj\AADObj\Program.cs:line 32
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

InnerException:

    public M1_DocumentElements(Session session)
        : base(session)

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